Bugfix: state not persisted. FRA lang update

FIX: languages now changeable again; however not refreshing correctly
yet
LNG: Updated French language
FIX: tab state was not correctly persisted
FIX: encoding of quotes in fixed in lslang strings
FIX: date intervals now corectly recognised in in-place edits
FIX: task state not updated correctly when clicking the star button
CLN: refactoring and cleanup in js file, logical ordering of events